| 摘要 |
Apparatus for deriving gradient vectors for use in the spatial interpolation of a digital video signal comprises a high pass filter (10) for filtering the scan lines of an input field of the video signal, a plurality of parallel processing channels comprising respective low pass filters (11) for filtering the high pass filtered video signal, an interpolator (13) for horizontally interpolating the scan lines of the input field of the video signal in at least some of the channels, a circuit (14, 15, 16, 17) for calculating pixel by pixel of the low pass filtered video signal the correlation for a range of pixel offsets, and a selector (18) for selecting for each pixel of the video signal the gradient vector corresponding to the correlation which is of maximum value. Interpolator apparatus and a television standards converter are also disclosed. |
